Raikkonen said he had a "good feeling" about the race and Hamilton is also wary of the threat from Red Bull's Max Verstappen and Daniel Ricciardo, who start third and fourth and have shown good race pace so far this weekend.
Vettel needed an engine change to his Ferrari after the last practice at Sepang on Saturday and immediately suffered a problem which could not be fixed in the first qualifying session. "We hope Seb will make a good recovery but it's not going to change my race".
Earlier, Vettel had clocked a 1m31.261s on the Pirelli super-soft compound tyres to finish the day 0.604 seconds clear of Raikkonen up front, while Mercedes had a scrappy session.
Vettel, whose retirement in Singapore last time out left him 28 points behind Hamilton in the standings, was unable to complete a lap in Q1 on Saturday and will therefore start from the back of the grid. Nor for the Malaysians themselves because of the troubled financial situation here, or Liberty Media, who do not regard it as the sort of race they really want on the calendar.
"We had no idea how it was going to go today", said Hamilton.
"I'm very grateful. It's always a special thing to be able to extract a little bit more out of the auto than it's particularly willing to go".
"I'm sorry what happened to Sebastian but we somehow turned it around, it is a real surprise to be up here with these guys". I hope our vehicle has moved in the right direction for the race run but we will see tomorrow.
MERCEDES boss Toto Wolff does not want to get carried away as his team prepare for the final Petronas Malaysia Formula 1 Grand Prix race at the Sepang International Circuit this weekend.
Having qualified on pole in Singapore, the stage was set for Vettel to retake the championship lead he had squandered for the first time in 2017. "It made it very, very tricky to put the laps together but fortunately for the last two laps I think it was okay".
"For sure it's not what you want, especially on a day when you feel you've got it in you and in the auto". "I've just got to make sure I keep performing as I have been".
"Not at all, I don't feel like I need to either", he said.
"Today we arrived and the vehicle was much better, it still looked like the Ferraris were a bit ahead so we had some big calls to make".